Obturating cartridge



May 31, 1960 J. F. OBRIEN 2,933,458

OBTURATING CARTRIDGE Filed Feb. 16, 1956 s Sheets-Sheet 1 INIVENTOIIQ.Jcfhn F. [I ETIEH WZQLQAZIQW H770 R Wsrs,

May 31, 1960 J. F. O'BRIEN 2,938,458

OBTURATING CARTRIDGE 3 Sheets-Sheet 2 Filed Feb. 16. 1956 INVENTOR. vJul-1n EL O'Brien BY 4f. 5% Q aw. fix.

May 31, 1960 J. F. O'BRIEN I 2,938,458

- .YOBTURATING CARTRIDGE Filed Feb. 16, 1956 s Sheets-Sheet s IN VENTOR.

John E. U'E'JriEn M 5 M Q flTrOR NEYS.

' John F. OBrien, Springfield, Mass., assignor to the United States ofAmerica as represented by the Secretary of the Army Filed Feb. 16, 1956,Ser. No. 566,052

1 Claim. (Cl. 102-38) (Granted under Title 35, US. Code (1952), sec.266) The invention described herein may be manufactured and used by orfor the Government for governmental purposes without the payment ,of anyroyalty thereon.

My invention relates to a cartridge for a gun and more particularly to acartridge having a neck disposed for elongation to form a gas seal withthe barrel of the gun.

Guns, such as the revolver-type automatic gun, include a barrel and adrum with cartridge discharge chambers rotatable with respect to thebarrel. Discharge gases escape through the necessary clearance spacebetween the barrel and the drum to heat the drum, and the rate ofoperation of the gun is limited by the overheating of the drum whichcauses premature ignition of the cartridges therein.

Obturating sleeves slidable in the chambers have proven to be among themost successful means to decrease the leakage of discharge gases throughthe clearance space, but eventually the sleeves themselves become heatedand transfer heat to the drum.

It is an object of my invention to provide disposable obturating devicesfor such a gun.

Another object of my invention is to provide such a gun with obturatingcartridges.

A further object of my invention is to provide cartridges having casesextensible for'obturation.

A still further object of my invention is to provide cartridges disposedfor obturation to bridge the clearance space between the drum and barrelresponsive to the discharge of the cartridges.

An additional object of my invention is to provide cartridges with caseshaving sleeves therein for obturafion. 4

Other aims and objects of my invention will appear from the followingexplanation.

In carrying out my invention several modifications of obturatingcartridges are provided in which the cases of the cartridges areextendable for contact with the breech end of the barrel to bridge thespace between the barrel and the chamber-carrying member.

In one of the modifications the necks of the gases are provided withperipheral corrugations which are disposed for deformation by theprojectiles to extend the necks into engagement with the barrels, upondischarge of the cartridges, to bridge the clearance spaces between thebarrels and the drums.

In another embodiment of my invention the forward ends of the necks ofthe cartridges are beveled inwardly for extension into engagement withthe barrels by the projectiles during the discharge thereof from thecartridges.

In another embodiment of my invention the necks of cartridges areprovided with telescopic portions which are extendable into engagementwith the barrels during discharge of the cartridges.

In yet another embodiment of my invention sleeves within the necks ofcartridges are forwardly slidable responsive to the discharge of thecartridges for engagement with the barrels.

For a more complete understanding reference is made 2,938,458 PatentedMay .31, 1960 to the accompanying drawings of several forms of myinvention in which:

Fig. 1 is a cutaway elevation of one embodiment of my invention inclosedin a cartridge chamber of a gun disposed in the discharge stationthereof;

Fig. 2 is a view showing the embodiment illustrated in Fig. 1 after thedischarge;

Fig. 3 is a cutaway elevation of a second embodiment of my inventiondisposed in a discharge station chamber of a gun; A

Fig. 4 is a view showing the embodiment illustrated in Fig. 3 after thedischarge;

Fig. 5 is a cutaway elevation of a third embodiment of my inventiondisposed in a discharge station chamber of a gun;

Fig. 6 is a view showing the embodiment illustrated in Fig. 5 after thedischarge;

Fig.7 is an exploded perspective view of the cartridge shown in Fig. 5;

Fig. 8 is a cutaway elevation of a fourth embodiment of my inventiondisposed in a discharge station chamber of a gun; and

Fig. 9 is a view showing the embodiment illustrated in Fig. 8 after thedischarge.

Shown in Fig. 1 is a cartridge 12 which is provided with a case 14having a neck 15 which case is axially coextensive to a chamber 16 of agun 18 having a barrel 20. Barrel 20 and chamber 16 are in axialalignment in the battery station thereof with a clearance space 22therebetween. Neck 15 includes annular corrugations 24 which arelongitudinally spaced therealong in the front portions of such neck forengagement by a projectile 17 inclosed within such neck. Thecorrugations 24 are formed to reduce the length of neck 15 an amountequal to the width of space 22 so that, when projectile 17 is propelledforwardly in the neck responsive to the discharge of cartridge 12, thecorrugations are engageably deformed beyond the elastic limits thereofto lengthen the neck sufiiciently to bridge space 22, as shown in Fig.2, and provide substantially gas-tight connection between the inside ofcase 14 and the bore of barrel 20.

In the embodiment of Fig. 3, a cartridge 26 axially coextensive to thechamber 16 is provided with a case 28, a neck 29 and a forward portion30 of the neck inwardly beveled as shown in such figure. velopedlengthof neck 28 includes the width of space 22 and such neck isextendable to bridge the space 22 during discharge of cartridge 26 whenportion 30 is pressed into alignment with the remaining portion of neck28 by the engagement of the discharged cartridge projectile as shown inFig. 4.

The embodiment of Fig. 5 shows a cartridge 42 with a case 44 axiallycoextensive to chamber 16 and having a neck with a stub portion 46corresponding to the neck of a conventional cartridge for gripping therear end of projectile 17. The remaining portion of the neck comprises aferrule 48 beveled at the rear end to conform to the angle of a shoulder50 extending forwardly from case 44 to stub portion 46. Ferrule 48includes tabs 52 pressed inwardly to lightly grip stub portion 46 andretain ferrule 48 thereon for storage of the cartridges and to maintainthe ferrule within chamber 16 during rotation of chamber 16.

A shoulder 54 is provided in ferrule 48 for impingement thereupon ofgases to drive ferrule 48 to a forward position and bridge clearancespace 22 responsive to discharge of cartridge 42, and a shoulder 56 isprovided on stub portion 46 for engagement with tabs 52 in the forwardposition of ferrule 48 for removal thereof from chamber 16 responsive toextraction of case 44 therefrom.

In the embodiment in Fig. 8 a cartridge 58 includes a The minimum dea 37 case 60 axially coextensive to chamber 16 which case is provided withan elongated neck 62 including an inner sleeve 64 of a resilientnonf-metallic material, such as nylon, and a liner 66 disposed.thereinfo inclosing projectile -17l Liner 66 includes aninner-jflange68' which extends radially outward to engage thevrear endofsleeve 64' v I V V r Gases impinge on flange 68 to propel liner 66' andsleeve 64 forwardly to bridge clearance space 22, responsive todischarge of cartridge 58.

Although several embodiments 'oithe invention have been described indetail herein, it is evident that many variations may be devised withinthe spirit and scope thereof and the following claim intended toincludesuch variations.

I claim: ,7 Y

A cartridge for a gun including a barrel and. a chamber for receivingthe cartridge, the chamber beingv disposed for axial alignment with thebarrel and for separation therefrom the width of a clearance space, thecartridge comprising a projectile, a case having. contact with the Wallsof the chamber when received. thereby, said case being provided with aforwardly extending neck for fully inclosing said projectile and havingthe same inside diameter as the maximum diameter portion of said pro- 3jectile for gripping retention thereof, annular corrugations formed insaid neck for swaging deformation between said projectile and the wallsof the chamber through radial forces applied by said projectile whenpropelled along said neck responsive to the discharge of the cartridge,said corrugations being provided with predetermined excess materialsufficient to bridge the space between the barrel and chamber when saidcorrugations are deformed by said projectile, and said corrugationsbeing,

disposed in spaced relationship along said neck and between the frontend thereof and the maximum diameter portion of said projectile fordeformation thereby to bridge the space before said projectile passesthereby.

References Cited in the file of this patent "UNITED STATES PATENTS GreatBritain of 19 14

